[SCSI] zfcp: remove union zfcp_req_data, use unit refcount for FCP co…

…mmands

o union zfcp_req_data removed
o increment unit refcount when processing FCP commands
 (This fixes a theoretical race: When all scsi commands of a unit
  are aborted and the scsi_device is removed then the unit could be
  removed before all fsf_requests of that unit are completely processed.)

Signed-off-by: Andreas Herrmann <aherrman@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>

drivers/s390/scsi/zfcp_aux.c

@@ -141,7 +141,7 @@ zfcp_cmd_dbf_event_fsf(const char *text, struct zfcp_fsf_req *fsf_req,
 
 	spin_lock_irqsave(&adapter->dbf_lock, flags);
 	if (zfcp_fsf_req_is_scsi_cmnd(fsf_req)) {
-		scsi_cmnd = fsf_req->data.send_fcp_command_task.scsi_cmnd;
+		scsi_cmnd = (struct scsi_cmnd*) fsf_req->data;
 		debug_text_event(adapter->cmd_dbf, level, "fsferror");
 		debug_text_event(adapter->cmd_dbf, level, text);
 		debug_event(adapter->cmd_dbf, level, &fsf_req,
@@ -167,14 +167,12 @@ void
 zfcp_cmd_dbf_event_scsi(const char *text, struct scsi_cmnd *scsi_cmnd)
 {
 	struct zfcp_adapter *adapter;
-	union zfcp_req_data *req_data;
 	struct zfcp_fsf_req *fsf_req;
 	int level = ((host_byte(scsi_cmnd->result) != 0) ? 1 : 5);
 	unsigned long flags;
 
 	adapter = (struct zfcp_adapter *) scsi_cmnd->device->host->hostdata[0];
-	req_data = (union zfcp_req_data *) scsi_cmnd->host_scribble;
-	fsf_req = (req_data ? req_data->send_fcp_command_task.fsf_req : NULL);
+	fsf_req = (struct zfcp_fsf_req  *) scsi_cmnd->host_scribble;
 	spin_lock_irqsave(&adapter->dbf_lock, flags);
 	debug_text_event(adapter->cmd_dbf, level, "hostbyte");
 	debug_text_event(adapter->cmd_dbf, level, text);
@@ -1609,7 +1607,7 @@ zfcp_fsf_incoming_els(struct zfcp_fsf_req *fsf_req)
 	u32 els_type;
 	struct zfcp_adapter *adapter;
 
-	status_buffer = fsf_req->data.status_read.buffer;
+	status_buffer = (struct fsf_status_read_buffer *) fsf_req->data;
 	els_type = *(u32 *) (status_buffer->payload);
 	adapter = fsf_req->adapter;
 

drivers/s390/scsi/zfcp_def.h

@@ -635,45 +635,6 @@ struct zfcp_adapter_mempool {
 	mempool_t *data_gid_pn;
 };
 
-struct  zfcp_exchange_config_data{
-};
-
-struct zfcp_open_port {
-        struct zfcp_port *port;
-};
-
-struct zfcp_close_port {
-	struct zfcp_port *port;
-};
-
-struct zfcp_open_unit {
-	struct zfcp_unit *unit;
-};
-
-struct zfcp_close_unit {
-	struct zfcp_unit *unit;
-};
-
-struct zfcp_close_physical_port {
-        struct zfcp_port *port;
-};
-
-struct zfcp_send_fcp_command_task {
-	struct zfcp_fsf_req *fsf_req;
-	struct zfcp_unit *unit;
- 	struct scsi_cmnd *scsi_cmnd;
-	unsigned long start_jiffies;
-};
-
-struct zfcp_send_fcp_command_task_management {
-	struct zfcp_unit *unit;
-};
-
-struct zfcp_abort_fcp_command {
-	struct zfcp_fsf_req *fsf_req;
-	struct zfcp_unit *unit;
-};
-
 /*
  * header for CT_IU
  */
@@ -781,33 +742,6 @@ struct zfcp_send_els {
 	int status;
 };
 
-struct zfcp_status_read {
-	struct fsf_status_read_buffer *buffer;
-};
-
-struct zfcp_fsf_done {
-	struct completion *complete;
-	int status;
-};
-
-/* request specific data */
-union zfcp_req_data {
-	struct zfcp_exchange_config_data exchange_config_data;
-	struct zfcp_open_port		  open_port;
-	struct zfcp_close_port		  close_port;
-	struct zfcp_open_unit		  open_unit;
-	struct zfcp_close_unit		  close_unit;
-	struct zfcp_close_physical_port	  close_physical_port;
-	struct zfcp_send_fcp_command_task send_fcp_command_task;
-        struct zfcp_send_fcp_command_task_management
-					  send_fcp_command_task_management;
-	struct zfcp_abort_fcp_command	  abort_fcp_command;
-	struct zfcp_send_ct *send_ct;
-	struct zfcp_send_els *send_els;
-	struct zfcp_status_read 	  status_read;
-	struct fsf_qtcb_bottom_port *port_data;
-};
-
 struct zfcp_qdio_queue {
 	struct qdio_buffer *buffer[QDIO_MAX_BUFFERS_PER_Q]; /* SBALs */
 	u8		   free_index;	      /* index of next free bfr
@@ -963,11 +897,12 @@ struct zfcp_fsf_req {
 	u32		       fsf_command;    /* FSF Command copy */
 	struct fsf_qtcb	       *qtcb;	       /* address of associated QTCB */
 	u32		       seq_no;         /* Sequence number of request */
-        union zfcp_req_data    data;           /* Info fields of request */ 
+        unsigned long          data;           /* private data of request */ 
 	struct zfcp_erp_action *erp_action;    /* used if this request is
 						  issued on behalf of erp */
 	mempool_t	       *pool;	       /* used if request was alloacted
 						  from emergency pool */
+	struct zfcp_unit       *unit;
 };
 
 typedef void zfcp_fsf_req_handler_t(struct zfcp_fsf_req*);